Per the State’s Validated Water Loss Audit Reporting Regulations (link):
§ 638.4. Technical Qualifications for a Water Audit Validator.
(1) A contractor working in the CA-NV AWWA Water Loss Technical Assistance Program (“Water Loss TAP”) performing water loss audit training and conducting audit validations.
(2) An individual who can demonstrate having conducted water loss audits in accordance with the method specified in Section 638.2, and having conducted a minimum of 10 Level 1 audit validations in accordance with the Water Research Foundation Level 1 Water Audit Validation: Guidance Manual 4639A (Water Audit Validation).
(3) An individual certified by the CA-NV AWWA as a water audit validator